The utilization of zirconium and zirconium based alloys for the containment of halogen containing environments used in the production of olefins, alcohols, ethers, and olefin oxides from alkanes

ABSTRACT

This invention relates to a process for the production of olefins, alcohols, ethers, and olefin oxides from alkanes in a halogen, preferably bromine or chlorine, system, wherein there are halogenation (reaction of halogen with the alkanes), oxidation (reaction of alkyl halide with a metal oxide), neutralization (reaction of hydrogen halide and metal oxide), and regeneration (reaction of metal halide with air, oxygen, or other oxygen gas containing mixtures) reactions which take place in the process and that these reactions, at least, are carried out in reactors made from metallurgy including zirconium and/or zirconium-based alloys that contain varying amounts of alloying elements such as tin, niobium, chromium, iron, oxygen, and nickel. Preferably, this same metallurgy is used in the fabrication of separation and purification equipment for the process.

REFERENCE TO PRIOR APPLICATIONS

This application claims the benefit of U.S. Provisional application Ser.No. 60/555,476, filed Mar. 23, 2004.

FIELD OF THE INVENTION

This invention relates to a process for manufacturing olefins, alcohols,ethers, and olefin oxides from alkanes by mixing an alkane and halide inthe reactor to form alkyl halide and hydrogen halide wherein the alkylhalide is contacted with a metal oxide to form an olefin, alcohol,ether, or olefin oxide and metal halide. More particularly, thisinvention relates to a choice of materials for the reactors in whichthis process is carried out.

BACKGROUND OF THE INVENTION

The engineering considerations regarding the industrial handling ofhalogen or halogen-containing mixtures are not trivial. Material ofconstruction identification is critical for the commercial success of anew process chemistry involving halogens. For example, in MaterialsSelection for the Chemical Process Industries by C. P. Dillon, publishedby McGraw-Hill Inc. in 1992, there is a chapter on the production ofacetic acid wherein part of the process involves the carbonylation ofmethanol and carbon monoxide in the presence of an iodine-complexcatalyst. At page 176, it is stated that zirconium 702 is one of thematerials which could be used in the reactor and flash tank to cope withacetic acid and iodine compounds at 150° C.

U.S. Pat. Nos. 4,278,810 and 5,847,203 discuss the problems with brominecatalyzed reactions for the production of terephthalic acid. In column 1of both patents, it is stated that expensive titanium and titaniumalloys have been used as construction materials in such plants toaccommodate the corrosivity of the bromine systems. Both patents relateto process changes which allow the use of stainless steel instead oftitanium.

U.S. Pat. No. 4,330,676 describes another such process and at column 4states that when the catalyst contains a bromide, a material must beused for withstanding the resulting highly corrosive reaction mixtureand titanium is given as the example.

According to publicly available information (e.g., U.S. Pat. No.6,403,840 B1, U.S. Pat. No. 6,462,243 B1, U.S. Pat. No. 6,465,696 B1,U.S. Pat. No. 6,465,699 B1, U.S. Pat. No. 6,472,572 B1, U.S. Pat. No.6,486,368 B1, and U.S. Pat. No. 6,525,230 B2, etc., which are hereinincorporated by reference), a process exists which consists of mixing analkane and a halide in a reactor to form alkyl halide and hydrogenhalide. The isolated alkyl halide or the alkyl halide and hydrogenhalide mixture react with a metal oxide to produce the products(alcohols, ethers, olefins, or olefin oxide) and metal halide. The metalhalide is oxidized with oxygen or air to form the original metal oxideand halide, both of which are recycled.

The hydrogen halide and/or the alkyl halide, when contacted with a metaloxide, will likely produce byproducts/products such as water andhydrogen halide. The combination of these constituents reacted attemperatures above 100° C. results in an environment that is highlycorrosive to most of the commonly used metals such as carbon steel,stainless steels, and duplex stainless steels. This type of environmentis especially corrosive in areas in which a liquid aqueous phase mayexist. Some of the more exotic metals that been proposed for this typeof environment (See U.S. Pat. No. 5,847,203, U.S. Pat. No. 4,330,676,and U.S. Pat. No. 4,278,810) are titanium and Hastelloy C. However,recently generated test data presented in Example 1 below indicate thatHastelloy C, or more generically, the nickel-chrome-molybdenum alloyfamily, affords very little resistance to corrosion under conditionswhich simulated the corrosive conditions that are anticipated in thisprocess environment.

According to the documents discussed above, titanium has been used toovercome the corrosivity of bromine reaction mixtures. Titanium is areactive metal and it relies heavily on the integrity of a protectiveoxide layer to prevent corrosion damage. Within the process environmentin the present process, there is an inherent presence of nascent, orunassociated, hydrogen atoms. Nascent hydrogen is known to penetrate theprotective oxide layer and migrate into the matrix of a base metal. Ifenough hydrogen penetrates into the base metal, internal metal hydridesmay form and these are often detrimental to the mechanical properties,as well as to the metal's ability to resist corrosion. This damagemechanism is commonly referred to as hydride embrittlement.

Historically, hydride embrittlement has been recognized as a problem inmany titanium applications. However, the likelihood of hydrideembrittlement of titanium is difficult to precisely quantify. Controlledlaboratory testing of this phenomenon is very difficult since the onsetof hydride formation may take one year or longer.

SUMMARY OF THE INVENTION

In one embodiment, the present invention relates to a process for theproduction of olefins, alcohols, ethers, and olefin oxides from alkanes(paraffins) in a halogen, preferably bromine or chlorine, system,wherein there are halogenation (reaction of halogen with the alkanes),oxidation (reaction of alkyl halide with a metal oxide), neutralization(reaction of hydrogen halide and metal oxide), and regeneration(reaction of metal halide with air, oxygen, or other oxygen gascontaining mixtures) reactions which take place in the process and thatthese reactions, at least, are carried out in reactors made frommetallurgy including zirconium and/or zirconium-based alloys thatcontain varying amounts of alloying elements such as tin, niobium,chromium, iron, oxygen, and nickel. Preferably, this same metallurgy isused in the fabrication of separation and purification equipment for theprocess.

Another embodiment of the present invention describes a process for theproduction of alcohols, olefins, ethers, and olefin oxides from alkaneswhich comprises the steps of:

-   -   a) halogenating an alkane to produce a mixture of alkyl halides        (mono-haloalkanes and possibly multi-haloalkanes), unreacted        alkanes, and hydrogen halide, preferably wherein the        halogenation step may be carried out thermally and/or        catalytically;    -   b) oxidizing the alkyl halide (or a subset of the alkyl halides        such as primary mono-haloalkanes), optionally together with the        hydrogen halide, with a metal oxide to produce the reaction        products and metal halide, wherein the hydrogen halide is        optionally separated;    -   c) if the hydrogen halide is separated in step b), neutralizing        it with a metal oxide to produce a metal halide; and    -   d) regenerating the metal halide(s) from the oxidation and        neutralization steps b) and c) to metal oxide and halogen using        oxygen, air, or a gas mixture containing oxygen gas (these        mixtures may include blends of oxygen with nitrogen, argon, or        helium) such that the halogen and metal oxide may be recycled        for use in the process; wherein these steps are carried out in        equipment which is made from metallurgy which includes zirconium        and/or zirconium based alloys. The zirconium-based alloys may        contain varying amounts, preferably from 0.01 to 3% by weight of        the total weight of the alloy, of alloying elements such as tin,        niobium, chromium, iron, oxygen, and nickel. Preferably, other        steps of the process where halogen and water may coexist are        also carried out in equipment made with such metallurgy.        Preferably, this same metallurgy is used in the fabrication of        separation and purification equipment for the process.

In another embodiment, the invention is a process for the production ofalpha olefins. The process converts branched or n-alkanes to branched orlinear alpha olefins (AO) of the same carbon number. The halogenation,oxidation, neutralization, and regeneration reactions, at least, arecarried out in reactors made from the metallurgy described in thepreceding embodiment.

In a further embodiment, the invention is a process for the conversionof linear, branched or a mixture of linear and branched alkanes intoalpha olefins. It comprises the steps of:

-   -   a) halogenating linear alkanes, branched alkanes, or a mixture        of linear and branched alkane(s) to produce a mixture of primary        mono-haloalkanes (i.e., alkanes with one halogen attached in the        primary position), internal mono-haloalkanes (i.e., alkanes with        one halogen attached somewhere other than the primary position),        unreacted alkanes, hydrogen halide, and possibly        multi-haloalkanes (i.e., alkanes with 2 or more halogens        attached), preferably wherein the halogenation may be carried        out thermally or catalytically;    -   b) separating the primary mono-haloalkanes from the mixture of        step a) by distillation or other appropriate separation step(s);    -   c) separating the hydrogen halide produced in the halogenation        step a) and neutralizing it with a metal oxide or mixture of        metal oxides to produce a partially halogenated metal oxide        and/or metal halide or mixture of partially halogenated metal        oxides and/or metal halides which are then converted for recycle        to halogen and metal oxide (or mixture of metal oxides) using        air, oxygen, or gas mixtures containing oxygen gas (these        mixtures may include blends of oxygen with nitrogen, argon, or        helium);    -   d) oxidizing the separated primary mono-haloalkane with a metal        oxide or combination of metal oxides to convert the aforesaid        primary mono-haloalkane to a mixture of products that contains        alpha olefins, unconverted primary mono-haloalkanes, and        possibly other reaction products (such as internal olefins,        primary alcohols and internal alcohols), and a partially        halogenated metal oxide and/or metal halide or a mixture of        partially halogenated metal oxides and/or metal halides;    -   e) separating and regenerating the partially halogenated metal        oxide and/or metal halide or mixture of partially halogenated        metal oxides and/or metal halides from step d) to a metal oxide        or mixture of metal oxides and molecular halogen (such as Cl₂)        by reaction with air, oxygen, or gas mixtures containing oxygen        gas (these mixtures may include blends of oxygen with nitrogen,        argon, or helium) wherein the halogen produced and/or the metal        oxide may be recycled; and    -   f) removing the unreacted primary mono-haloalkane from the        reaction mixture and then purifying the alpha olefin; wherein        steps a), c), d), and e) are carried out in equipment which is        made from metallurgy which includes zirconium and/or zirconium        based alloys. The zirconium-based alloys may contain varying        amounts, preferably from 0.01 to 3% by weight of the total        weight of the alloy, of alloying elements such as tin, niobium,        chromium, iron, oxygen, and nickel. Preferably, other steps of        the process where halogen and water may coexist are also carried        out in equipment made with such metallurgy. Preferably, this        same metallurgy is used in the fabrication of separation and        purification equipment for the process.

In another embodiment, there is described a process to convert alkanesto primary alcohols of the same carbon number wherein the halogenation,oxidation, and regeneration, at least, are carried out in reactors madefrom metallurgy including zirconium and zirconium-based alloys thatcontain varying amounts of alloying elements such as tin, niobium,chromium, iron, oxygen, and nickel. Preferably, this same metallurgy isused in the fabrication of separation and purification equipment for theprocess.

This embodiment describes a process for the production of primaryalcohols from alkanes which comprises the steps of:

-   -   a) halogenating a linear or branched (or mixture of linear and        branched) alkane to produce a mixture of primary        mono-haloalkanes (i.e., alkanes with one halogen attached in the        primary position), internal mono-haloalkanes (i.e., alkanes with        one halogen attached somewhere other than the primary position),        unreacted alkanes, hydrogen halide, and possibly        multi-haloalkanes (i.e., alkanes with 2 or more halogens        attached), preferably wherein the halogenation may be carried        out thermally or catalytically;    -   b) separating the primary mono-haloalkanes from the mixture of        step a) by distillation or other appropriate separation step(s);    -   c) oxidizing the separated primary mono-haloalkane with a metal        oxide or combination of metal oxides and water (and possible        hydrogen halide) to convert the aforesaid primary        mono-haloalkane to a mixture of products that contains primary        alcohols, unconverted primary mono-haloalkanes, and possibly        other reaction products (such as internal alcohols and/or        olefins), and a partially halogenated metal oxide and/or metal        halide or a mixture of partially halogenated metal oxides and/or        metal halides;    -   d) separating and regenerating the partially halogenated metal        oxide and/or metal halide or a mixture of partially halogenated        metal oxides and/or metal halides to a metal oxide or mixture of        metal oxides and molecular halogen (such as Cl₂) by reaction        with air, oxygen or gas mixtures containing oxygen gas (these        mixtures may include blends of oxygen with nitrogen, argon, or        helium), wherein the halogen produced and/or the metal oxide may        be recycled; and    -   e) removing the unreacted primary mono-haloalkane from the        reaction mixture and then purifying the primary alcohol; wherein        steps a), c) and d) are carried out in equipment which is made        from metallurgy which includes zirconium and/or zirconium based        alloys. The zirconium-based alloys may contain varying amounts,        preferably from 0.01 to 3% by weight of the total weight of the        alloy, of alloying elements such as tin, niobium, chromium,        iron, oxygen, and nickel. Preferably, other steps of the process        where halogen and water may coexist are also carried out in        equipment made with such metallurgy. Preferably, this same        metallurgy is used in the fabrication of separation and        purification equipment for the process.

DETAILED DESCRIPTION OF THE INVENTION

The process of the present invention is applicable to the production ofolefins, alcohols, ethers, and olefin oxides from alkanes of almost anycarbon number. The product carbon numbers of primary interest are C₁ toC₂₀ and the product carbon numbers of particular interest are C₈ to C₁₈.

Alkanes are converted via halogenation to a mixture of primarymono-haloalkanes, internal mono-haloalkanes, unreacted alkanes, hydrogenhalide, and possibly multi-haloalkanes. Halogenation may preferably becarried out thermally or catalytically (for example in a conventionalreactor, in a catalytic distillation (CD) column, etc.), and with orwithout the use of a support intended to promote shape selectivity. Forthe production of primary alcohols and alpha olefins, halogenationprocesses that preferentially produce primary mono-haloalkanes (e.g.,catalytic halogenation at lower temperatures, thermal halogenation athigher temperatures, etc.) are preferred. Preferred halogens arechlorine, bromine, and iodine. For the production of primary alcoholsand alpha olefins, chlorine is preferred. For other olefins, alcohols,ethers, and olefin oxides, bromine may be preferred.

Thermal halogenation is carried out by introducing the halogen and thealkane to a reactor. The reaction temperature may be from 100° C. to400° C. As stated above, catalytic halogenation may be carried out atlower temperature, such as from 25° C. to 400° C. Catalysts which may beused include compounds of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe,Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, B Al, Ga, In, Tl, Si,Ge, Sn, Pb, P, Sb, Bi, S, Cl, Br, F, Sc, Y, Mg, Ca, Sr, Ba, Na, Li, K,0, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Er, Yb, Lu and Cs or mixturesthereof.

For the case of primary alcohols and alpha olefins, the mixture ofprimary mono-haloalkanes, other mono- and multi-haloalkanes, unreactedalkanes, and hydrogen halide is transferred to a separation train thatisolates the primary mono-haloalkanes from the mixture. To produceprimary alcohols and/or alpha olefins, it is preferred to direct onlyprimary mono-haloalkanes to the oxidation reactor. The separation trainmay include (1) a distillation or other appropriate separation step torecover hydrogen halide, (2) a distillation or other appropriateseparation step (or multiple steps) to separate unreacted alkanes,multi-haloalkanes, and mono-haloalkanes, and (3) an additionalseparation step to separate primary mono-haloalkanes from internalmono-haloalkanes. The unreacted alkanes may be recycled to the primaryhalogenation reactor. The multi-haloalkanes may be recycled to theprimary halogenation reactor or may be recycled to a disproportionationreactor to convert some of the multi-haloalkanes to mono-haloalkanes. Ifa disproportionation reactor is used, the resulting reaction mixture ofmulti-haloalkanes and mono-haloalkanes is then recycled to theseparation train. The internal mono-haloalkanes may be recycled to theprimary halogenation reactor or may be recycled to an isomerizationreactor to convert some of the internal mono-haloalkanes to primarymono-haloalkanes. If an isomerization reactor is used, the resultingreaction mixture of internal alkyl halides and primary alkyl halides isthen recycled to the separation train.

Suitable separation schemes include distillation, adsorption, meltcrystallization, and others. For the primary and internalmono-haloalkanes separation, distillation and melt crystallization areparticularly preferred. For some carbon chain lengths (C₆-C₁₀),distillation is preferred because of differences in boiling points (andas result, relative volatilities). For other carbon chain lengths(C₁₂-C₁₆), melt crystallization is preferred because of the substantialfreezing point difference between primary and internal mono-haloalkanes.

The hydrogen-halide produced in the halogenation reactor may beseparated and neutralized with a metal oxide to produce a metal halide.Engineering configurations to carry out this hydrogen halideneutralization process include a single reactor, parallel reactors, andtwo reactors (one to trap hydrogen halide and one to regeneratemetal-halide), among others. Using air, oxygen, or other oxygen gascontaining mixtures (these mixtures may include blends of oxygen withnitrogen, argon, or helium), this metal halide is converted(regenerated) to halogen and the original metal oxide both of which arepreferably recycled.

Another option for using the hydrogen halide is to send it to ametathesis reactor (also called an oxidation reactor), wherealkyl-halides are reacted with metal oxide as explained below. Metaloxides which may be used in this step and in the other metathesisreaction below, include oxides of the following metals: Ti, Zr, Hf, V,Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au,Zn, Cd, B, Al, Ga, In, Tl, Si, Ge, Sn, Pb, P, Sb, Bi, S, Cl, Br, F, Sc,Y, Mg, Ca, Sr, Ba, Na, Li, K, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Er, Yb,Lu, and Cs or mixtures thereof.

The alkyl-halide (primary mono-haloalkane for the production ofalpha-olefins and/or primary alcohols) that is isolated in theseparation train alone or produced in the halogenation reactor alongwith the hydrogen halide is sent into a metathesis reactor with aselected metal oxide or a combination of metal oxides to convert thealkyl-halide to a mixture of products. The product distribution ofolefins, alcohols, ethers, and/or olefin oxides depends on the metaloxide used in the metathesis reaction.

Water may be fed to the reactor to aid in the formation of alcohols byproviding an extra source of hydrogen and/or oxygen. The reactionconditions such as residence time, temperature, reaction phase(solid-gas, solid-liquid, etc.), and addition of water or hydrogenhalide are selected to maximize the desired product production. The samemetal oxide or combination of metal oxides may be able to producepreferentially different products (such as alcohols instead of olefins,ethers or olefin oxide) depending on the reaction conditions. Forexample, longer residence times, higher temperatures, and solid-liquidphase reaction tend to preferentially produce alcohols over olefins. Theaddition of water to the metathesis reaction may be crucial for theproduction of alcohols.

The metal oxide or metal oxides used in the metathesis reactor may ormay not be different from the one(s) used in the neutralization of thehydrogen halide. The metal oxide is partially (or totally) converted toa metal halide. A purification train is used to isolate the product.Suitable purification schemes include distillation, adsorption, meltcrystallization, and others. The unconverted alkyl-halides are recycledto the metathesis reactor.

The metal halide is regenerated to metal oxide and halide by using air,oxygen, or a mixture oxygen gas containing gas (these mixtures mayinclude blends of oxygen with nitrogen, argon, or helium). The liberatedhalogen is preferably recycled to the halogenation reactor. Theregeneration of metal halide to metal oxide and halide may beaccomplished with various reactor configurations including a separateregeneration reactor, in situ with a combined regeneration/metathesisreactor where the air/oxygen flow and primary alkane feed flow arealternated (for example, as described in U.S. Pat. No. 6,525,230, whichis herein incorporated by reference), in situ regeneration with amultiple metathesis reactor configuration in a fixed bed mode, etc.Irrespective of reactor design, type of metal oxide, or halogen,zirconium metallurgy is suited for the regeneration reactor.

The final product (olefins, alcohols, ethers or olefins) is purified ina separation train.

The present invention offers a family of suitable metals for thecontainment of the type of hot wet halogen containing environments(especially chlorine and bromine) that exist in parts of this process ofreacting alkanes to form olefins, alcohols, ethers and/or olefin oxides.This invention identifies this metallurgy as suitable for use in thefabrication of separation equipment that could be utilized in thepurification of above-mentioned products. The specific metallurgyidentified includes zirconium and zirconium based alloys that containvarying amounts of alloying elements such as tin, niobium, chromium,iron, oxygen, and nickel.

Generally, the alloying elements described above are present in thezirconium in amounts ranging from 0.01 to 3 percent by weight of thetotal alloy. A partial list of these types of zirconium alloys includeszirconium 702 (aka UNS Grade R60702), zirconium 704 (aka UNS GradeR60704), zirconium 705 (aka UNS Grade R60705), zirconium 706 (aka UNSGrade R60706), zirconium 702-S, Zr-2.5 Nb (aka UNS Grade R60901),Zircaloy-2 (aka UNS Grade R60802), and Zircaloy-4 (aka UNS GradeR60804).

The chemical requirements of many of these zirconium based alloys areprovided in the American Standards for Testing and Materials (ASTM)standard B 551. The chemical composition requirements for some of thesematerials expressed in weight percent (wt %), as provided in ASTM B-551are as follows: zirconium 702—99.2 minimum wt % Zr+Hf, 0.05 maximum wt %C, 0.2 maximum wt % F+Cr, 0.005 maximum wt % H, 4.5 maximum wt % Hf,0.025 maximum wt % N, and 0.16 maximum wt % oxygen; zirconium 704—97.5minimum wt % Zr+Hf, 0.05 maximum wt % C, 0.2-0.4 wt % Fe⁺ Cr, 0.005maximum wt % H, 4.5 maximum wt % Hf, 0.025 maximum wt % N, 0.18 maximumwt % oxygen, and 1.0-2.0 wt % Sn; zirconium 705—95.5 minimum wt % Zr+Hf,0.05 maximum wt % C, 0.2 maximum wt % Fe+Cr, 0.005 maximum wt % H, 4.5maximum wt % Hf, 0.025 maximum wt % N, 2.0-3.0 wt % Nb, and 0.18 maximumwt % oxygen; and zirconium 706—95.5 wt % Zr+Hf, 0.05 maximum wt % C, 0.2maximum wt % Fe⁺ Cr, 0.005 maximum wt % H, 4.5 maximum wt % Hf, 0.025maximum wt % N, 2.0-3.0 wt % Nb, and 0.16 maximum wt % oxygen.

Zirconium 702-S is a designator assigned to a recently developedvariation on zirconium 702 that sets a more rigorous requirement on theamount of Sn that is allowed in the requirements for zirconium 702. Themaximum content of Sn that is allowed in zirconium 702-S is 0.25 wt %Sn. Otherwise, the chemical requirements for zirconium 702-S areidentical to zirconium 702. The chemical requirements for this new metalwere obtained from a zirconium manufacturer's website—www.wahchang.com.

Zircaloy-2 (aka UNS Grade R60802) and Zircaloy-4 (aka UNS Grade R60802)are both common zirconium-tin (Sn) alloys. The American Society ofMetals (ASM) Handbook, volume 2, provides a typical composition forthese zirconium-tin alloys as follows: Zircaloy-2—1.4 wt % Sn, 0.1 wt %Fe, 0.1 wt % Cr; 0.05 wt % Ni; 0.12 wt % 0, and the balance Zr; andZircaloy-4—1.4 wt % Sn, 0.2 wt % Fe, 0.1 wt % Cr, 0.12 wt % 0, and thebalance Zr.

Zr-2.5 Nb (aka UNS Grade R60901) is a common zirconium-niobium (Nb)alloy. The American Society of Metals (ASM) Handbook, volume 2, providesa typical composition for this zirconium-niobium alloy as follows:Zr-2.5Nb—2.6 wt % Nb, 0.14 wt % 0, and the balance Zr.

The hydrogen halide and/or the alkyl halide, when contacted with a metaloxide, may produce byproducts/products such as water and hydrogenhalide. The hot process environment required will contain water as wellas the halogen(s), preferably bromine or chlorine. The combination ofthese constituents reacted at temperatures above 100° C. results in anenvironment that is highly corrosive to most of the commonly used metalssuch as carbon steel, stainless steels, and duplex stainless steels. Theenvironment of this process is especially corrosive in areas in which aliquid aqueous phase may exist. Some of the more exotic metals that beenproposed for this type of environment (See U.S. Pat. No. 5,847,203, U.S.Pat. No. 4,330,676, and U.S. Pat. No. 4,278,810) are titanium andHastelloy C. However, recently generated test data presented in Example1 indicate that Hastelloy C, or more generically thenickel-chrome-molybdenum alloy family, affords very little resistance tocorrosion under conditions which are similar to the corrosive conditionsin the environment of this process. The results from these same testsindicate that zirconium based metals offer adequate corrosion resistanceand are suitable materials of construction for this processes.

A comparison of the chemical properties and industrial experiencebetween titanium and zirconium further supports the position thatzirconium and its alloys are more suitable alternatives for this processenvironment. Both of these metals are classified as reactive metals andthey rely heavily on the integrity of a protective oxide layer toprevent corrosion damage. Within this process environment there is aninherent presence of nascent, or unassociated, hydrogen atoms. Nascenthydrogen is known to penetrate the protective oxide layer and migrateinto the matrix of the base metal. The ability of the zirconium tofacilitate the transport of hydrogen harmlessly through the metal matrixis better than that of titanium. The solubility of hydrogen in zirconiumis much lower than that of titanium.

The degree of solubility of hydrogen in the base metals relates directlyto the susceptibility of the base metals to form internal metalhydrides, which are often detrimental to the mechanical properties, aswell as to the metal's ability to resist corrosion. This damagemechanism is commonly referred to as hydride embrittlement.

Historically hydride embrittlement has been a recognized problem in manytitanium applications. However, the likelihood of hydride embrittlementof titanium is difficult to precisely quantify. Controlled laboratorytesting of this phenomenon is very difficult since the onset of hydrideformation may take one year or longer. Consequently, much of the datathat relates to hydride embrittlement of titanium is anecdotally basedon field experiences. However a study of relevant case historiessuggests to us that titanium metal that is exposed to dry, or slightlywet, highly acidic environments is prone to this form of damage. Basedon this criterion, we consider hydride embrittlement of titanium to be asignificant concern for the present process environment.

Thus, it appears that titanium should not be chosen as the metallurgyused in the process of the present invention because of the significantrisk factor. Zirconium, with its ability to facilitate the transport ofhydrogen harmlessly through the metal matrix and the lower solubility ofhydrogen in zirconium, is a much better choice.

EXAMPLES

Short term corrosion testing was performed in an attempt to findacceptable materials for this process environment. These corrosion testswere conducted in four cells containing water that was saturated withbromine. Each of the cells were constantly stirred and maintained at ahigh enough pressure to ensure the water remained in the liquid state.The tests were run at two temperatures, 150° C. and 188° C. These testssimulated water condensation at those high temperatures.

Oxygen may have a very dramatic effect on the corrosion rates of manymetals. Since various areas of the proposed process will have varyingcontents of oxygen, one set of tests was initially purged of oxygen bydisplacement with nitrogen gas, while the second set allowed for thepresence of oxygen contamination.

The tests were originally scheduled to run for 10 days. Thethermocouples used to control the temperature of one of the test cellsfailed due to corrosion after only three days of operation. This forcedthe immediate shut down of this test cell. Upon inspection of thecoupons that were retrieved from this cell it was determined that theintegrity of the remaining test cells, which were constructed ofHastelloy C276, might have been compromised if the testing were tocontinue for the entire 10 day duration. Due to this concern the testsin the three remaining cells were subsequently terminated.

Although the test duration was abbreviated, the corrosion data reveals asignificant advantage in the corrosion resistance of Zirconium 702 incomparison to the more commonly used nickel and chrome alloys. The datafrom these tests are provided in the table below.

It should be noted that although this testing targeted a hotbromine/water environment, similar trends in data are expected for theanalogous chlorine based environment. TABLE 1 Corrosion Testing in HotAqueous Bromine Environments Oxygen Inches of Present Test CorrosionRate Metal Loss Test # Temperature (Yes/No) Metal Duration (1 mpy =0.001″ per year) per Year 1 188° C. Yes Type 304L SS 125 hrs 2372 mpy 2.37 2 188° C. Yes Hastelloy B2 125 hrs 443 mpy 0.44 3 188° C. YesHastelloy C276 125 hrs  86 mpy 0.09 4 188° C. Yes Inconel 625 125 hrs187 mpy 0.19 5 188° C. Yes Zirconium 702 125 hrs 0.32 mpy  0.0003 6 150°C. Yes Type 304L SS 125 hrs 1397 mpy  1.40 7 150° C. Yes Hastelloy B2125 hrs 586 mpy 0.59 8 150° C. Yes Hastelloy C276 125 hrs 104 mpy 0.10 9150° C. Yes Inconel 625 125 hrs 144 mpy 0.14 10 150° C. Yes Zirconium702 125 hrs 0.36 mpy  0.0004 11 188° C. No Type 304L SS 101 hrs 3126mpy  3.22 12 188° C. No Hastelloy B2 101 hrs 493 mpy 0.49 13 188° C. NoHastelloy C276 101 hrs 150 mpy 0.15 14 188° C. No Inconel 625 101 hrs331 mpy 0.33 15 188° C. No Zirconium 702 101 hrs 1.04 mpy  0.001 16 150°C. No Type 304L SS 101 hrs 543 mpy 0.54 17 150° C. No Hastelloy B2 101hrs 1160 mpy  1.16 18 150° C. No Hastelloy C276 101 hrs  38 mpy 0.04 19150° C. No Inconel 625 101 hrs  81 mpy 0.08 20 150° C. No Zirconium 702101 hrs 0.54 mpy  0.0005

1. A process for the production of olefins, alcohols, ethers, and olefinoxides from alkanes in a halogen system, wherein there are halogenation(reaction of halogen with the alkanes), oxidation (reaction of alkylhalide with a metal oxide), neutralization (reaction of hydrogen halideand metal oxide), and regeneration (reaction of metal halide with air,oxygen, or other oxygen gas containing mixtures) reactions which takeplace in the process and that these reactions, at least, are carried outin reactors made from metallurgy including zirconium and/orzirconium-based alloys that contain varying amounts of alloying elementssuch as tin, niobium, chromium, iron, oxygen, and nickel.
 2. The processof claim 1 wherein the zirconium-based alloys may contain varyingamounts, preferably from 0.01 to 3% by weight of the total weight of thealloy, of alloying elements such as tin, niobium, chromium, iron,oxygen, and nickel.
 3. A process for the production of alcohols,olefins, ethers, and olefin oxides from alkanes which comprises thesteps of: a) halogenating an alkane to produce a mixture of alkylhalides, unreacted alkanes, and hydrogen halide; b) oxidizing the alkylhalide, optionally together with the hydrogen halide, with a metal oxideto produce the reaction products and metal halide, wherein the hydrogenhalide is optionally separated; c) if the hydrogen halide is separatedin step b), neutralizing it with a metal oxide to produce a metalhalide; and d) regenerating the metal halide(s) from the oxidation andneutralization steps b) and c) to metal oxide and halogen using oxygen,air, or a gas mixture containing oxygen gas such that the halogen andmetal oxide may be recycled for use in the process; wherein these stepsare carried out in equipment which is made from metallurgy whichincludes zirconium and/or zirconium based alloys.
 4. The process ofclaim 3 wherein the gas mixture is selected from the group consisting ofblends of oxygen with nitrogen and/or argon and/or helium.
 5. Theprocess of claim 3 wherein the zirconium-based alloys may containvarying amounts, preferably from 0.01 to 3% by weight of the totalweight of the alloy, of alloying elements such as tin, niobium,chromium, iron, oxygen, and nickel.
 6. The process of claim 3 whereinthe metal halides produced in the oxidation and neutralization reactionsare different and they are regenerated independently.
 7. A process forthe production of alpha olefins from branched or n-alkanes of the samecarbon number in a halogen system, wherein there are halogenation(reaction of halogen with the alkanes), oxidation (reaction of alkylhalide with a metal oxide), neutralization (reaction of hydrogen halideand metal oxide), and regeneration (reaction of metal halide with air,oxygen, or other oxygen gas containing mixtures) reactions which takeplace in the process and that these reactions, at least, are carried outin reactors made from metallurgy including zirconium and/orzirconium-based alloys that contain varying amounts of alloying elementssuch as tin, niobium, chromium, iron, oxygen, and nickel.
 8. The processof claim 7 wherein the zirconium-based alloys may contain varyingamounts, preferably from 0.01 to 3% by weight of the total weight of thealloy, of alloying elements such as tin, niobium, chromium, iron,oxygen, and nickel.
 9. A process for the production of alpha olefinsfrom branched or n-alkanes of the same carbon number which comprises thesteps of: a) halogenating linear alkanes, branched alkanes, or a mixtureof linear and branched alkanes to produce a mixture of primarymono-haloalkanes, internal mono-haloalkanes, unreacted alkanes, hydrogenhalide, and possibly multi-haloalkanes; b) separating the primarymono-haloalkanes from the mixture of step a) by distillation or otherappropriate separation step(s); c) separating the hydrogen halideproduced in the halogenation step a) and neutralizing it with a metaloxide or mixture of metal oxides to produce a partially halogenatedmetal oxide and/or metal halide or mixture of partially halogenatedmetal oxides and/or metal halides which are then converted for recycleto halogen and metal oxide (or mixture of metal oxides) using air,oxygen, or gas mixtures containing oxygen gas; d) oxidizing theseparated primary mono-haloalkane with a metal oxide or combination ofmetal oxides to convert the aforesaid primary mono-haloalkane to amixture of products that contains alpha olefins, unconverted primarymono-haloalkanes, and possibly other reaction products, and a partiallyhalogenated metal oxide and/or metal halide or a mixture of partiallyhalogenated metal oxides and/or metal halides; e) separating andregenerating the partially halogenated metal oxide and/or metal halideor mixture of partially halogenated metal oxides and/or metal halidesfrom step d) to a metal oxide or mixture of metal oxides and molecularhalogen by reaction with air, oxygen, or gas mixtures containing oxygengas wherein the halogen produced and/or the metal oxide may be recycled;and f) removing the unreacted primary mono-haloalkane from the reactionmixture and then purifying the alpha olefin; wherein steps a), c), d),and e) are carried out in equipment which is made from metallurgy whichincludes zirconium and/or zirconium based alloys.
 10. The process ofclaim 9 wherein the gas mixture is selected from the group consisting ofblends of oxygen with nitrogen and/or argon and/or helium.
 11. Theprocess of claim 9 wherein the zirconium-based alloys may containvarying amounts, preferably from 0.01 to 3% by weight of the totalweight of the alloy, of alloying elements such as tin, niobium,chromium, iron, oxygen, and nickel.
 12. The process of claim 9 whereinthe metal halides produced in the oxidation and neutralization reactionsare different and they are regenerated independently.
 13. A process toconvert alkanes to primary alcohols of the same carbon number whereinthere are halogenation (reaction of halogen with the alkanes), oxidation(reaction of alkyl halide with a metal oxide), and regeneration(reaction of metal halide with air, oxygen, or other oxygen gascontaining mixtures) reactions which take place in the process and thatthese reactions, at least, are carried out in reactors made frommetallurgy including zirconium and/or zirconium-based alloys thatcontain varying amounts of alloying elements such as tin, niobium,chromium, iron, oxygen, and nickel.
 14. The process of claim 13 whereinthe zirconium-based alloys may contain varying amounts, preferably from0.01 to 3% by weight of the total weight of the alloy, of alloyingelements such as tin, niobium, chromium, iron, oxygen, and nickel.
 15. Aprocess for the production of primary alcohols from alkanes whichcomprises the steps of: a) halogenating a linear alkane, branchedalkane, or mixture of linear and branched alkanes to produce a mixtureof primary mono-haloalkanes, internal mono-haloalkanes, unreactedalkanes, hydrogen halide, and possibly multi-haloalkanes; b) separatingthe primary mono-haloalkanes from the mixture of step a) by distillationor other appropriate separation step(s); c) oxidizing the separatedprimary mono-haloalkane with a metal oxide or combination of metaloxides and water (and possible hydrogen halide) to convert the aforesaidprimary mono-haloalkane to a mixture of products that contains primaryalcohols, unconverted primary mono-haloalkanes, and possibly otherreaction products, and a partially halogenated metal oxide and/or metalhalide or a mixture of partially halogenated metal oxides and/or metalhalides; d) separating and regenerating the partially halogenated metaloxide and/or metal halide or a mixture of partially halogenated metaloxides and/or metal halides to a metal oxide or mixture of metal oxidesand molecular halogen by reaction with air, oxygen or gas mixturescontaining oxygen gas, wherein the halogen produced and/or the metaloxide may be recycled; and e) removing the unreacted primarymono-haloalkane from the reaction mixture and then purifying the primaryalcohol; wherein steps a), c) and d) are carried out in equipment whichis made from metallurgy which includes zirconium and/or zirconium basedalloys.
 16. The process of claim 15 wherein the zirconium-based alloysmay contain varying amounts, preferably from 0.01 to 3% by weight of thetotal weight of the alloy, of alloying elements such as tin, niobium,chromium, iron, oxygen, and nickel.
 17. The process of claim 15 whereinthe gas mixture is selected from the group consisting of blends ofoxygen with nitrogen and/or argon and/or helium.